But maybe you've found yourself asking more than once, “What exactly is a rail-with-trail?”

Simply, a rail-with-trail is a trail alongside an active rail line. Flipping the script on what we traditionally think of as “rail-trails” (repurposing disused rail corridors), rails-with-trails combine a number of transportation, recreation and safety benefits in one linear space. In more densely developed urban areas, in particular, collocating rail service with pathways for walking and biking makes tremendous sense, and is a creative and efficient solution to some of our most pressing transportation and environmental problems.

The two characteristics of rails-with-trails that most often surprise people are—

1. There are so many of them. There are more than 217 rail-trails in America, which means that more than one in every 10 rail-trails actually parallels an active line at some point. They are in our wide open rural spaces and through the heart of our biggest cities. Just like traditional rail-trails, all sorts of people use them for all sorts of reasons.

2. They have a remarkable safety record.We’ve studied activity on rails-with-trails over the last 20 years, and in all that time, there have been only two serious accidents involving a trail user and a train. Rail-with-trail has been proven to be infinitely safer than trails alongside roadways, partly because the movement of a train is so predictable.

A third characteristic, and this is where it gets interesting for people in Florida, is that rails-with-trails help rail transit systems function better by helping more people get to the stations without the massive costs and impacts of more parking and more traffic congestion.

That’s why pretty much every new transit system being built these days is incorporating biking and walking pathways into it; planners know that people these days get around by using a combination of modes, and increasingly, that doesn’t include a car. Innovative and forward-thinking systems like Miami’s M-Path, the West Line Rail in Denver, Colo., the Beltline in Atlanta, Ga., and the groundbreaking Tilikum Crossing in Portland, Ore., were all designed so biking and walking pathways connect to transit stations and from there connect to local neighborhoods, shops and employment centers.

If the All Aboard Florida project does not include a rail-with-trail system, unfortunately the result will be a transportation system of the 1950s rather than one suited to the Florida of the future. A $2.5 billion infrastructure project that will be out of date the minute it opens doesn’t seem like a great use of public funds, public land or public infrastructure.

On the other hand, the inclusion of a parallel pathway for walking and biking immediately improves the efficiency and capacity of the system, makes it serve a much broader population and mitigates a whole host of anticipated negative impacts, from traffic congestion to the division of neighbors and the deterioration of green space.

Not to mention, most of the communities along the route already have plans in place for biking and walking trails along the corridor!

This is why RTC believes a rail-with-trail is a must-have, and not an optional extra, for All Aboard Florida.